Here's the passage where Satan tempts Jesus in this way:
Matthew 4:8-10 Again, the devil took him to a very high mountain and showed him all the kingdoms of the world and their glory. And he said to him, “All these I will give you, if you will fall down and worship me.” Then Jesus said to him, “Be gone, Satan! For it is written, “‘You shall worship the Lord your God and him only shall you serve.’”
Notice how Satan is offering the kingdoms of the world, not the riches. Satan doesn't have banks of gold, but what he can do is lie and blind people to the truth.
2 Corinthians 4:3-4 ESV And even if our gospel is veiled, it is veiled to those who are perishing. In their case the god of this world has blinded the minds of the unbelievers, to keep them from seeing the light of the gospel of the glory of Christ, who is the image of God.
He has a deceptive stranglehold on the evil rulers of the world and that is what he was offering to Jesus; or at least what he was claiming to offer.
Also, stories about people mystically "selling their soul" to the devil are pure fantasy tales and not in scripture, unless to "sell one's soul" just means to do evil and revel in it--a lot of that happens.